Insulating-lining.



G. L. SHERMAN. INSULATING LINING.

APPLICATION FILED JUNE 30, 1913.

I: AIWRNEYS CHARLES L. SHERMAN, OF PHILADELPHJIA, PENNSYLVANIA INSULATING-LINING.

Specification of Letters ratent.

Patented Feb. 3, 1914.

Application filed June 30, 1918. Serial No. 776,498.

To (ZZZ whom it may concern:

Be it known that I, CHARLES L. SHnRMArI, a citizen of the United States, residing 1n the city and county of Philadelphia, State of Pennsylvania, have invented a new and useful Insulating-Lining, of which the following is a specification.

My invention relates to a novel construction of an insulating sleeve or lining of the character employed in incandescent lamp sockets to separate the metallic outer shell from the current carrying parts of the' socket.

It has heretofore been proposed in this art to line the metallic shell which surrounds other metallic parts serving to carry or regulate an electric current with an insulating sleeve or lining stamped, formed or pressed out from sheets of fiber or similar material shaped so as to form an approxiniately cylindrical lining of the proper shape, said insulating lining being made of a single piece of suitable material such as fiber, hard rubber or the like of varying diameter, said lining being made by taking tubes of insulating material, cutting them into suitable lengths and submitting them to the action of dies. These insulating fibrous linings which have been heretofore employed have been open to objection, since it has been sometimes found in practice to be impractical to make said linings invariably fit thev shell with just the requisite closeness to prevent the linings falling out and. still allow of their ready insertion and removal. Furthermore, if such fibrous linin g of the prior art under certain conditions fitted the shell with just the proper closeness, such requisite close fit would not be maintained under the varying conditions arising from moisture and temperature or climatic conditions and with these linings there was therefore constant danger of the lining dropping out of the shell, which has been a recognized defect in this class of linings, to remedy which attempts have heretofore been made without satisfactory results. To obviate these defects, it has been heretofore proposed to provide an insulating sleeve or lining for such incandescent lamp sockets, composed of paper or similar elastic insulating material having a portion of its periphery of larger diameter than the part of the shell within which it is to fit, so that as the lining is inserted in the shell, this elastic or resilient portion will be compressed and by this elasticity will maintain the requisite frictional contact with the inner periphery of the shell. This latter class of elastic linings has been formed from paper tubing, consisting of closely wound layers of paper formed by the action of less expense than the fibrous lining hereto fore employed, to which I have referred. I have, however, found by practical use that even in these last mentioned paper linings, which are'formed witha reduced end portion so'proportioned, that said reduced end is designed to spring outward somewhat, to give the requisite frictional contact with the inclosing shell, that owing to climatic. and other conditions even these devices fail to obviate the above defects and I have therefore devised the present invention, which consists of an insulating sleeve or lining, comprising a tube of suitable elastic or resilient material, which is so proportioned with respect to the coacting metallic shell, that all parts of the lining are out of contact with the interior surface of the shell with the exception of one or more frictional contact points which are pressed outwardly, preferably from the larger periphery of the lining, so as to extend entirely around the outer periphery of said lining, the requisite frictional contact between the outer surface of the lining and the inner juxtaposed portion of the shell being attained by reason of the enlarged annular beads or protuberances upon that portion of the lining preferably of largest diameter, and to this end my invention consists of a novel construction of an insulating sleeve or lining comprising anelastic tube having end portions of different diameters and an annular bead or beads or their equivalent suitably formed upon preferably the larger portion of the lining, So as to extend entirely around the outer periphery of said lining, whereby the requisite frictional contact between the lining and the surrounding shell is obtained, the portion of the lining of smallest diameter being spaced entirely away from the inner surface of the inclosing shell.

It further consists of other novel features masses of construction, all will be hereinafter fully set forth.

For the purpose of illustrating my inven tion, I have shown in the accompanying drawings one form thereof which is at pres ent preferred by me, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities oil which my invention consists can be variously arranged and organized and that myinven- 'tion is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described.

Figure 1 represents a side elevation of one form of an insulating lining, embodying my invention. Fig; 2 represents a sectional view of another lining, embodying my invention, placed in position Within the surrounding metallic shell of the incandescent lamp.

Similar numerals of reference indicate corresponding parts in the figures.

Referring-to the drawings, in carrying out my invention for the purposes of cheapness, l form-the elastic insulating sleeve or lining from a paper tube, consisting of closely Wound layers of paper closely compacted to gether, which after having been subjected to the action of suitable dies assumes the shape seen in Figs. 1, 2 or 3.

In the embodiment seen in Fig. l, the lin ing 1 has an end port-ion 2 of larger diameter and the portion 3 of smaller diameter, both portions 2 and 3 being shaped, so that they are of slightly less diameter, than the metallic shell 8 into'which they will be inserted, the orticns 2 and 3 being joined by the shoulder 4. At a suitable step in the manu facture or formation of thelining by means of dies or otherwise, I provide in any suitable manner the frictional retaining device,

- and that the frictional cen at l.

which comprises an annular bead or enlargement 6 integral with the lar or portion 2 of the lining and may be'locate in any desired proximity to the shoulder 4 above which is the reduced portion 3, said head extending entirely and continuously around the outer periphery of said lining.

In the construction seen in Fig. 2, 1 form preferably integral with. the portion 2 of largest diameter, a plurality of annular enlargements, rings or beads it, which are located below the shoulder 4 above which is the reduced portion 3, said beads extending entirely and continuously around the outer periphery of the lining;

In all the embodiments of my invention it will be apparent that the insulating lining proper is throughout the greater-portion its outer periphery spaced to slight away from the metallic shell 8 mclosi tain the lining "within the seen is or,

reason of the annular heads 6 or a plurality of heads 7, or their equivalents, as 'Wlll. be evr dent to those skilled in this art, the lining thus termed having the requisite elasticity and compressibility and being especially,

adapted for use in incandescent lamp sockets to meet all practical requirements and being so constructed that the lining for the outer shell will be at all times retained in the shell and under all conditions by the frictional contact devices without danger of'dropping out and without offering undue ijesistance to its removal I am aware that the patent to Painter #718,378, granted January 13, 1903, discloses the employment of a lining of fiber, rubber or similar insulatingtmgterial,whiph is adapted to contact for the greater portion of its outer periphery with the inclosing metallic shell, and that it is a common right to employ a lining of this character by reason of the decision in General Electric Company '08. Yost- Electric Manufacturing Com.- pany, 139 Fed.Rep.,p. 568, wherein a "prodnot of the general character referred to was held to be public property and also it is a common right to employ a paper tube having its diameter reduced for a portion of its length, either alone or in combination wlt-h a metallic shell, in view of the decision in Marshall cs. Pettingelloindrews Company, L64 Fed, 862, and I hereby make no claim per so to the use of a fiber, rubber or paper lining or to the mode of manufacturing the same, my presentinvention being diiierentiated from the above devices and relating solely to an insulating lining of materially less diameter than thejuxt-aposed periphery of the metallic shell, which is to fit'said lining, the latter being held in position within stud shell solely by reason of the frictional contact of an annular head or beads or their eanivalent, whereby the lining will be ret'alhed within the outer shell at all times and under all conditions without danger of popping out and without-offering undue resistance to its removal. I

it desire to lay special emphasis upon the tact that theportion of the smaller diameter 3 is entirely out of contact with the inclosing shell 8, as is the portion 2 of greater diameter, the shell being retained in osition solely by the frictional contact or the bulged portions '8 or 7. In practice 1 prefor to employ the construction. seen in Figs. lor 2, since a linin with the resilient projiection extending larger diameter is more effective than one having longitudinal corrugations, since in the latter construction the convened longiportions contact with the shell lon gitudinally and since the lining is flexible, it is not held in place as satisfactorily as the resilient convened portions extend iametrically around its around the larger diameter of the lining, as i seen in Figs. 1 and 2, in which construction j a greater area or contacting surface is afforded between the lining and shell, where- I by the lining is resiliently engaged with the shell in a more uniform and rigid manner. 1 which frictional contact is maintained until 5 the lining is entirely removed from the shell. l

I have not deemed it necessary to describe i in detail the various steps employed in the formation of my novel insulating lining having the integral continuous bulges or annular beads thereon, as the same, ymr .w. form no part of the present invention, and l have also deemed it unnecessary to descri detail any specific means or mech anism for forming the continuous annular frictional bead 6 or the plurality of annular l frictional beads 7, as I do not desire to be limited to any particular means or steps whereby the same may be produced. I have also deemed it unnecessary to indicate the slots and openings usually formed in the linings or sockets, as these are of course made to suit the socket in which the lining is to be used.

It will now be apparent that I have deviseda novel and useful construction of an insulatinglining, which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present instance, shown and described a 5 preferred embodiment thereof which has been found in practice to give satisfactory l and reliable results, it is to be understood I that the same is susceptible of modification i in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages. 1

Having thus described my invention. what i I claim as new and desire to secure by Letters Patent, is

1. In an incandescent lamp socket, an insulating lining adapted to be inserted Within an outer shell, consisting of a tube of elastic and compressible material having thereon, an outwardly projecting bead extending around the outer periphery of said lining.

An insulating lining consisting of a tube having end portions of different diameters and composed of elastic material, the larger of said portions being provided with a continuous outwardly projecting bead extending entirely aroundvthe outer periphery of said lining.

3. The combination of a metallic shell, with an insulating sleeve consisting of an elastic compressible paper tube of less diameter than said shell, the larger portion of said tube being provided with a continuous outwardly projecting bead extending en tircly around the outer periphery of said tube and adapted to engage the juxtaposed contiguous inner portion of the inclosing shell.

4. In an incandescent lamp socket the combination of a metallic shell, with an insulating sleeve consisting of an elastic, compressible paper tube of less diameter than said shell, the larger portion of said tube being provided with a plurality of continuous outwardly projecting beads extending entirely around the outer periphery of said tube adapted to engage the juxtaposed con tiguous inner portion of the inclosing shell.

CHARLES L. sHERMANQ Witnesses E. HAYWARD l anum us, G. D. McVAY. 

